EN
A biological valuation system to assess the value associated with ecosystem stability and richness (and not that from the point of view of users) is proposed to provide scientific decision support for marine protected areas and marine spatial planning. The system is based on the assessment of individual species and habitat/species assemblages. An extensive set of recently collected (2007–08) and archival (1970 –2000) data on the occurrence of marine benthos was analysed for the PolishMarine Areas. Based on matching data sets of sediments, the euphotic zone, temperature and salinity, as well as fetch and sea current values, a GIS model was used to visualise the results; a map indicates the two areas which are considered to be biologically the most valuable (Puck Bay and the stony shallows of the central coast).